Cardiac-arrest, exposure to high voltage power lines, and other trauma to the body can result in ventricular fibrillation. Ventricular fibrillation is the rapid and uncoordinated contraction of the myocardium of the heart. The use of external defibrillators to restore the heart beat to its normal pace through the application of an electrical shock is a well recognized and important tool in resuscitating patients. External defibrillation is typically used in emergency settings in which the patient is unconscious.
Automatic External Defibrillators (AEDs) are used by first responders such as police officers, fire fighters, and emergency medical technicians to resuscitate victims of sudden cardiac arrest. Studies have shown that the chances of successfully resuscitating a patient decrease approximately ten percent per minute following the onset of sudden cardiac arrest. Accordingly, a victim of sudden cardiac arrest will most likely not survive unless a trained rescuer responds in less than ten minutes after the cardiac arrest occurs and successfully defibrillates the heart.
Automatic External Defibrillators are designed to be very easy to use so that rescuers without extensive medical backgrounds can successfully resuscitate victims of sudden cardiac arrest. AEDs are currently being carried in emergency vehicles such as police cars, paramedic vehicles, and fire trucks. AEDs are also being widely deployed in areas where large numbers of people gather, such as at sports stadiums, gambling casinos, etc.
In one study, AEDs were used to assess cardiac rhythm in 18 patients with a mean age of 12.1.+-.3.7 years. The cardiac rhythms were analyzed 67 times and included ventricular fibrillation (25), asystole/pulseless electrical activity (32), sinus bradycardia (6), and sinus tachycardia (4). The AEDs recognized all nonshockable rhythms accurately and advised no shock. Ventricular fibrillation was recognized accurately in 22 (88%) of 25 episodes and advised or administered a shock 22 times. Sensitivity and specificity for accurate rhythm analysis were 88% and 100%, respectively. One patient with a nonshockable rhythm survived, whereas 3 of 9 patients with ventricular fibrillation survived.
The data from this study furnish evidence that AEDs provide accurate rhythm detection and shock delivery to children and young adolescents. AED use is potentially as effective for children as it is for adults.
Accordingly, there is a need in the industry for AEDs adapted to deliver therapy to pediatric patients. Preferably, such adaptation should not require extensive modification to existing AEDs.